Process of smelting aluminum ores.



UNITED STATES PATENT OFFICE.

FRANK J. TONE, OF NIAGARA FALLS, NEW YORK, ASSIGNOR TO THE CARBORUNDUMCOM- PANY, OF NIAGARA FALLS, NEW YORK, A CORPORATION OF PENNSYLVANIAPROCESS OF SMELTING ALUMINUM ORES.

Specification of Letters Patent.

Patented Dec. s, 1908.

To all whom it may concern:

agara Falls, Niagara county, New York, have invented a new and usefulProcess of Smelting Aluminum Ores, of which ,the following is a full,clear and exact description.

This invention refers to the smelting of aluminum ores, particularly tosilicatesof aluminum and has for its object the production therefrom ofnew and useful substances containing silicon or aluminum or both ofthese elements.

Aluminum silicate is an ore of aluminum of wide occurrence and is thebasis of all true clays. I have discovered that by smelting this ore inthe electric furnace together with a' suitable reducing agent, it ispossible to reduce the silicon without reducing the aluminum and that byproper regulation of temperature it is possib e to fuse the remainingaluminum compound to a form of fused aluminum oxid, having greathardness and valuable abrasive qualities. I have also discovered thatthe reduction of the silicon is facilitated by adding to the mixturebase' metal or ore such as iron or manganese WlllCh alloys with thesilicon and makes the reduction of the latter more complete. In

proportion, making an iron silicid of corre-- spondingly greater ironcontent. If the base metalliferous material is added in the form of anoxid, additional carbon must be added to reduce this to metallic form.When this charge is smelted in the electric furnace, a reaction occursin accordance with the following equation:

The aluminum silicate is dissociated and the silicon is reduced toelemental form uniting with the iron to form an iron silicid. 'lherebeing insufiicient carbon to reduce the alu- Y minum, this does not partwith its oxygen Be it known that I, FRANK J. TONE, of N1-v and is'transfo'rmml into fused oxid of filll. minum of crystalline structure.

Any ordinary form of arc furnace with verpot or chamber is suitable forcarrying out this recess. The charge mixture is fed into the urnacearound the electrodes and as the finished product accumulates and buildsup under the arc, the electrodes are raised to allow the finishedproduct to form a pig or ingot of considerable size. After a sullieientamount of mixture has been smelted to form allowed to cool. '1 e ironsilicid being heavier than the alumina, has a tendency to settle to thebottom of the furnace from which it may be. ta ped at intervals duringthe run. It also agglbmerates in nodules of greater or less size throubout the finished product. After the ingot ias cooled it is broken upand the silicid is separated from the alumina. This may be done invarious ways. Preliminary separation may be made by hand after which Iprefer tocrush the finished product and separate the grains of aluminafrom the silicid by concentration. The separation may be facilitated ifthe silicon and base metal are combined in roper roportion to form adisinte rating a loy. have found that by adding t e base metalliferousmaterial as manganese or manganese ore in the proportions to form asilicid containing 45 to 50 percent. manganese the alloy is very friableand on fine powder. per cent. iron is of similar character. Otherdisintegrating alloys may be produced in similar manner and for the samepurpose of facilitating se aration of finished products.

The si icids produced in this process are useful for'various pur oses,such as refining of iron and steel, and t e alumina is useful as anabrasive and also as an ore for the production of metallic aluminum.

I claim:

1. The method of transforming aluminum silicate into a materialpossessing great hardness and abrasive properties, which consists inmaking a mixture of aluminum silicate, carbon and base metalliferousmaterial, the amount of carbon being sufficient to reduce the siliconbut insufficient to reduce the aluminum, and the amount of basemetaltical electrodes depending into the furnace an ingot of a sizeconvenient to handle, the furnace run is stop ed and the fused mass 1sexposure to air tends to disintegrate into a An iron silicid containing35 liferous material being sufiicient to form a occur and thenseparating the fuse alumina and the silicon alloy of the resultantproduct.

2. The method of transforming num silicate into a material possessinggreat hardness and abrasive properties, which consists in making amixture of aluminum silicate, a base metalliferous material, and areducing agent in such proportions that the alumisilicon will be reducedwithout reducing the g aluminum, the proportions of the basemetalliferous metal being such as to form a disintei grating alloy withthe reduced silicon, subfleeting the mixture to electrically developedeat, and allowing the mixture to cool and i disintegratin actlon tooccur, and then separating the 'used alumina and the silicon alloy ofthe resultant product.

' In testimony whereof, I have hereunto set I my hand.

FRANK J. TONE.

Witnesses:

. CHARLES OHORMANN, 1 S. S. DIEMER.

